Damage caused by the Stuxnet computer worm could cause "another Chernobyl" at Iran's first nuclear power plant, Russian nuclear scientists have warned.
The plant, situated at the Gulf port of Bushehr, is due to go live this summer but Russian experts working at the facility claim it faces disaster if Iran's government pushes ahead with its current tight schedule.
The Bushehr plant was originally commissioned in the 1970s by Iran's former leader, the Shah. After decades of delay, the country's new leadership is demanding that scientists stick to the deadline set last year.
Last December, a German security expert declared that the Stuxnet attack had set Iran's nuclear ambitions back by two years. But speaking earlier this month, Iran's foreign minister Ali Akbar Salehi - who also heads the country's Atomic Energy Organisation - rejected calls for the Bushehr plant's opening to be postponed.
"All the rumours related to the Westerners' claims that Stuxnet had caused damage to the nuclear plants are rejected," he said.
Russian experts are now so alarmed by Iran's apparent disregard for nuclear safety issues that they have asked the Kremlin to intervene.
In a report seen by the Daily Telegraph, the scientists accuse bosses at the plant of "disregard for human life", and say they that they "cannot guarantee safe activation of the reactor".
Iran admitted last November that computer systems at the Bushehr reactor had been affected by the Stuxnet virus, in what is widely regarded as the world's most successful cyber attack.
According to a report in the New York Times at the weekend, Stuxnet was developed jointly by US and Israeli intelligence officials at the top-secret Dimona reactor in Israel's Negev desert.
While Iran insists its nuclear programme is aimed at peaceful, civilian use, Western intelligence officials believe it could be used to produce nuclear weapons.